Trust has become an important issue for e-commerce and other applications, particularly for mobile computing devices such as notebook computers. Specifically, as the mobility of the computing platform increases, it becomes susceptible to theft, with stolen data often representing a bigger loss than the hardware itself, because the data can include, e.g., user identity information, credit card information, and so on.
With this in mind, the Trusted Computing Platform Alliance (TCPA) has been formed to develop a specification for a trusted computing platform. Using a hardware security module (actually, a microcontroller) known as the Trusted Platform Module (TPM) that is soldered to the motherboard of the computing platform, the TCPA establishes what can be thought of as a platform root of trust that uniquely identifies a particular platform and that provides various cryptographic capabilities including hardware-protected storage, digital certificates, IKE (Internet Key Exchange), PKI (Public Key Infrastructure), and so on. Essentially, to overcome the vulnerability of storing encryption keys, authentication certificates, and the like on a hard disk drive, which might be removed or otherwise accessed or tampered with by unauthorized people, encryption keys, certificates, and other sensitive data is stored on the secure TPM.
The various keys including the endorsement keys are unique to the TPM. The endorsement keys are either generated at manufacturing time outside the TPM and then sent (“squirted”) to the TPM for storage, or the keys are generated within the TPM itself. The keys can be used to in turn encrypt other keys for various purposes, thereby extending the trust boundary as desired.
The validity of the endorsement keys is attested to by an electronic document known as an endorsement certificate that is provided by someone other than the entity that provides the keys and that is generated using the TPM public half of the endorsement key. In other words, to ensure the validity of the TPM, the user of the TPM/host device may require an endorsement certificate, a process the details of which are currently undefined. As recognized herein, the provision of the endorsement certificate must be accomplished in a way that complicates hacking or that otherwise complicates compromising the process of certifying the validity of the TPM (and, hence, that complicates unauthorized attempts to defeat the security provided by the TPM).